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  • 301.
    Eriksson, Annie
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Lööf, Elisabeth
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Nilsson, Filippa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Eckert Elfving, Niklas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Chowdhury, Sadat
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Oscarson, Simon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Jonsson, Tove
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    QC upgrade and verification for HS-Lenti RT Activity Kit2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this project was to present a cost-efficient quality control routine to ensure thefunctionality of HS-Lenti RT Activity Kit, an ELISA-based kit produced by Cavidi AB, thatscreens for lentiviruses such as HIV. Two main methods for quality control are presented inthis report; acceptance sampling and Statistical Process Control (SPC). Acceptance samplingis a process where only parts of a batch are tested in order to determine whether or not thewhole batch should be accepted or rejected. SPC centers around monitoring an ongoingprocess by using statistical measures and charts which visualize variations in these measuresover time. Initially, using an acceptance sampling plan is recommended as the primaryapproach. SPC charts can then be set up using the data generated from the acceptancesampling, and be used in parallel with the acceptance sampling for some time until they canbe implemented to a wider extent. This report also presents different options forimmunoassay data processing. Bayesian methods of estimating analyte concentrations inunknown samples are highlighted as promising candidates in improving the performance andusability of the kit. The report also includes a customer requirements analysis, based on aconducted survey, that investigates the demands researchers within Uppsala University placeon products similar to HS-Lenti RT Activity Kit. The data which the analysis is based on wasobtained from an online questionnaire and three interviews. An ethical analysis regarding thequality control approach and survey is included as well.

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    Survey
  • 302.
    Eriksson, Elin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Development and comparison of three immunoassay formats to screen for total anti-adeno-associated virus serotype 2 antibodies in human serum using the Gyrolab immunoassay platform2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Recombinant adeno-associated virus vectors are one of the most promising gene delivery tools for applications within gene- and cell therapy. The high level of wild-type adeno-associated virus infections in humans is a limitation due to the pre-existing immunity against the vector or its transgene product. An important tool to develop effective and safe therapies is the ability to measure the pre-existing immune responses against the virus capsids in humans.

    This master thesis at Gyros Protein Technologies aimed to investigate if the Gyrolab immunoassay system can be used to screen for pre-existing anti-capsid immunity in human sera by optimizing and evaluate three different assay formats: an indirect assay, a generic anti-AAV adsorption assay and a bridging assay. The evaluation focused on immunity against adeno-associated virus serotype 2. All immunoassay formats performed well and depending on application, the different formats offers different advantages. The generic anti-AAV adsorption assay offers the ability to easily screen for several viral serotypes without having to label the capsid, and the bridging assay provides high sensitivity. When screening 31 individual human sera, 58% were positive using the indirect assay and the generic anti-AAV adsorption assay and 65% using the bridging assay format. Provided, is automated and high throughout immunoassays where 16 individuals can be screened in one-two hours. It is shown that all three immunoassay formats can be used to screen for anti-adeno-associated virus antibodies, even though further optimization, cut off development and a larger data set is needed to obtain a fully sophisticated screening tool.

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  • 303.
    Eriksson, Emil
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Exploration behaviour, habitat choise and territorial defence behaviour in captive reared and released naive adult tawny owls.2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Territoriality is a behaviour that has evolved to secure resources for survival and reproduction. We know very little about how individuals become territorial, and such information may be important in release programs for threatened species. In this paper I study the establishment of a territory and the habitat choice of captive-raised tawny owls, a year-round territorial bird of prey. The aim is to find out how fast these naïve tawny owls claim their own territory and what type of environment they most likely do establish territory within. In total 19 tawny owls were released, four of these owls were equipped with remote downloading GPS loggers attached as backpacks to study their habitat choice and explorative behaviour. My results suggest that 82 % of the owls successfully establish territory on average 22 days after the release. I was not able to download data from the GPS loggers with the downloading station, which is most likely due to the GPS signal having difficulties traveling through the closed forest which is interfering with the signal. This indicates that this type of automatic downloading GPS is not suitable for this type of forest-dwelling species. A large proportion of the owls became territorial very fast after they have been released, showing strong territoriality instinct in these naive individuals. This may suggest that released naïve tawny owls can successfully claim a territory and thereby contribute to the pool of reproductive individuals. 

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  • 304.
    Eriksson, Hanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Uppsala universitet.
    Implementation of thiamine pyrophosphate (TPP) riboswitches as synthetic biosensors and regulatory tools in cyanobacteria2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The natural occurrence of the non-mevalonate (also called MEP after the compound methyl-erythriol phosphate) pathway in the model cyanobacterium Synechocystis sp. PCC 6803 allows for biosynthesis of various high-value terpenoid compounds. An important co-factor of this pathway is thiamine pyrophosphate (TPP), coenzyme to the 1- deoxy-D-xylulose-5-phosphate synthase (DXS) reaction in the initial step of the MEP pathway. Concurrently, TPP biosynthesis derives partially from 1-deoxy-D-xylulose phosphate, the product of DXS. This makes TPP a potentially significant measure of MEP pathway activity, and thus terpenoid productivity. The implementation of a molecular biosensor for TPP could be a promising approach towards on-line assessment and feedback regulation of MEP pathway activity and this application is therefore investigated in this work. Riboswitches have been suggested as versatile RNA-based tools for biotechnological applications in bacteria, including various cyanobacterial species. However, TPP-responsive riboswitches have not been addressed in cyanobacteria thus far. This project therefore aims at the evaluation and implementation of TPP-responsive riboswitches in Synechocystis, using a yellow fluorescent reporter protein as quantitative readout of translational regulation. Native putative OFF-switches from two cyanobacterial species are investigated along with one synthetic ON-switch, originally based on the native riboswitch from E. coli. The induction effects are assessed on both RNA and protein level for both TPP and its precursor thiamine. The synthetic riboswitch is found to be effective in Synechocystis and is further examined for its dynamic range. Several protocols for fluorescence and transcript level experiments are developed. Several continuation experiments are suggested, including further investigation of the cyanobacterial OFF-switches.

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    Master thesis Hanna Eriksson
  • 305.
    Eriksson, Jenny
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Fasth, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Orrenius, Cecilia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Milica, Plavsic
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Yuan Andersson, Linnéa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Westholm, Marcus
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Goodbye E.coli: Alternativa endotoxinfria produktionssystem till Escherichia coli2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Affibody is interested in replacing Escherichia coli as the production system for Affibody®-molecules in order to reduce the amount of resources needed for the purification step. The aim of this report is to present relevant endotoxin-free alternatives that would suit production. Affibody®-molecules are proteins that have similar specificity as antibodies used in biopharmaceuticals, but have the advantage of being smaller. Since E. coli is the current production organism, the product is contaminated with immunogenic endotoxins which cause a high demand of resources during the purification process, something Affibody wants to reduce. The results presented in this report were achieved by means of a systematic literature study, divided into one general phase and two specific search phases. In the general literature search phase we were solely concerned with finding endotoxin-free expression systems. In the specific search phases the expression systems found were narrowed down in two steps based on criteria such as potential of scale-up > 1000 L, approval from the European Medicines Agency and the Food and Drug Administration, cost and productivity. Finally, only three candidates remained that met all requirements. The information found pertaining to the expression systems was presented in a spreadsheet, as were the different sources used. The nominated endotoxin-free candidates suggested to replace E. coli are Pichia pastoris, Chinese Hamster Ovary (CHO) cells and the Baculovirus Expression Vector System (BEVS). The candidates were then weighed against each other in an analysis based on the given criteria. We concluded that all three candidates satisfy the criteria and are suitable replacements for Affibody to use instead of E. coli.

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  • 306.
    Eriksson, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Identification of mRNA expressions as biomarkers of environmental pollutants in the great pond snail (Lymnaea stagnalis)2022Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The great pond snail, Lymnaea stagnalis is considered a sensitive species to environmentalpollution and is used in ecotoxicology testing. The snail is naturally found in the environment inthe Holarctic realm in Europe, northern America and Asia but also in some parts of Australia. Itis a species of great interest for ecotoxicology studies and is used in research where commonendpoints are reproduction, mortality and immune responses. In this study we wanted to establisha method of using gene expressions in L. stagnalis as biomarkers of chemicals and pollutants inSTP effluent water. The study was conducted in two different experiments where gene expressionfor elongation factor 1a (ef1a), nuclear hormone receptor 3d (nr3d), cytochrome p450 3 (cyp3),metallothionein (mt), catalase (cat), glutathione peroxidase (gpx), and yolk ferritin (yf) from thehepatopancreas of L. stagnalis were measured. In experiment 1, animals were exposed tocadmium, 17α-ethinylestradiol, diclofenac, tramadol, PCB and a solvent control for seven days.In experiment 2 one group of animals were exposed to regular STP effluent water (UT), onegroup exposed to regular STP with an additional treatment of ozone (OZ), one group exposed toregular STP with an additional treatment of granulated active carbon (GAC) and finally, one lastgroup exposed to tap water (KV) as a control. The exposures lasted three weeks. In experiment 1,yf was upregulated 1.4-fold in snails exposed to PBC. In experiment 2, differences between thewaters were seen in the expressions of cyp3, gpx and yf. The expression of cyp3 was lower in theGAC group compared to the other groups. There was a difference in the expression of gpxbetween GAC and OZ but not compared to regular effluent water, UT or the tap water, KV. Theexpression of yf was higher in KV, but not different between the other groups. In summary, the yfgene expression in L. stagnalis is altered by PCB. There were also measurable effects of theexpression of cyp3 and gpx in snails exposed to effluent water treated with GAC. Conclusions ofthe results are difficult to draw but the changes in gene expressions indicates that L. stagnalis is apromising candidate as a model organism to gene expressions as biomarkers. Further studies arehowever needed to refine the method.

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  • 307.
    Eriksson, Linnea
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Deep Learning Models for Profiling of Kinase Inhibitors2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    With the advent of fluorescence microscopy and image analysis, quantitative information from images can be extracted and changes in cell morphology can be studied. Microscopy-based morphological profiling assays with multiplexed fluorescent dyes, like Cell Painting, can be used for this purpose. It has been shown that morphological profiles can be used to train AI models to classify images into different biological mechanisms. Hence, the goal of this project was to study the possibilities for Deep Learning models and Convolutional Neural Networks to distinguish between different classes of kinase inhibitors based on their morphological profiles. Three different Convolutional Neural Network architectures were used: ResNet50, MobileNetV2, and VGG16. They were trained with two different inputs and two different optimisers: Adam and SGD. Also, a comparison between the performances with and without Transfer Learning through ImageNet weights was executed. The results indicate that MobileNetV2 with Adam as an optimiser performed the best, with a micro average of 0.93 and higher ROC areas compared to the other models. The study also highlighted the importance of utilizing Transfer Learning.

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    Appendix A
  • 308.
    Eriksson, Linnea
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Identifiering av LPS-bindning till cellytor hos olika blodkroppstyper i sötvattenskräfta2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Both vertebrates and invertebrates use an innate system to recognise and fight pathogens such as bacteria. In this study, I focus on the methods the freshwater crayfish Pacifastacus leniusculus possess to inhibit the Gram-negative bacteria via LPS-recognition. Previous research has shown that this crayfish has certain proteins that can bind LPS, and that its bloodcells, the haemocytes, have an important role in this. However, scientists have yet to find evidence that LPS can bind the outside of these cells, similar to LPS-binding in humans. By bleeding crayfish and treating the cells with a primary and secondary antibody I could observe LPS-binding to the outside of granular haemocytes. This suggests there might be a protein positioned in or on the membrane of these types of cells that can bind LPS, which initiates the defence mechanisms. 

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  • 309.
    Eriksson, Matilda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Wells, Alva
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Frey, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Johansson, Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Pettersson, Gabriel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Sjöberg, David
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Navigating Large-Scale Plasmid DNA Purification: A Recommendation of Current and Future Downstream Purification Solutions2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Previous small-scale methods for plasmid DNA (pDNA) purification fail to meet theindustry’s demand for sufficient quantities. Greater volumes of bacterial lysates are a consequence of larger volumetric fermentations and traditional large-scale down-stream purification processes have some disadvantages and limitations. The market is believed to continue to expand, hence the need for efficient, cost-effective, andscalable purification processes becomes apparent. A crucial trade-off exists between pDNA yield and purity, necessitating careful consideration in chromatographic pu-rification steps. Each step enhances purity while likely sacrificing yield. In order to achieve a higher degree of pDNA yield, optimal purification entails a single chro-matographic step, specifically anion-exchange chromatography (AEX) in combina-tion with filtration. Alternatively, a two-step purification approach involving AEX followed by hydrophobic interaction chromatography (HIC) is recommended to elim-inate complementary impurities and achieve a high level of purity. Furthermore, the utilization of monolithic chromatographic supports is suggested to facilitate the sug-gested purification strategies. This is due to monoliths promoting higher binding capacities, ensuring robust and consistent results even at high flow rates.

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    Navigating Large-Scale Plasmid DNA Purification
  • 310.
    Eriksson, Olof
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Ecological Botany.
    Niva, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Caruso, Alexandro
    Use and abuse of reindeer range2007Book (Other academic)
    Abstract [en]

    In consequence of variations in geology and soils, in climate, and in its wide extent in longitude, latitude and altitude, the Scandinavian mountain chain exhibits major variations in natural conditions. Nature is constantly influenced by processes that include both natural forces and human activity.

    In the early 1990s, there was an intense media debate about current damage to the montane vegetation, which many believed they could observe.

    In 1992, the World Wide Foundation for Nature, WWF, invited representatives of responsible authorities, reindeer-husbandry interests, voluntary conservation bodies and interested researchers to a conference, which, somewhat erroneously, came to be called the 'Reindeer grazing conference', but which included a spectrum of factors that can affect the montane vegetation.

    One result of this conference was that, in 1993, WWF initiated a research project, extending over several years, intended to provide information about temporal changes in montane vegetation.

    Experimental areas distributed along the Swedish mountain chain were selected: the southernmost are on Fulufjället in Dalama, and the northernmost are ea. 15 km S of Tavvavuoma in Swedish Lapland. (Some placenames are given in modern North-Saamish spelling in Appendix 2) The vegetation types studied were Grass heath, Meadow with low herbs, Dry heath, Birch forest-heath type with lichens and Birch forest-heath with mosses. These cover all major montane areas and are important grazing areas for reindeer.

    At all study sites, six adjacent plots were selected, half of which were fenced to deny access to larger herbivores, and half were left open for grazing by all herbivores. The composition of plant communities in the field, bottom and tree layer in plots was estimated in 1995-96, and re-estimated three to four years later.

    Generally, marginal or no effects of enclosure were seen on the vegetation communities, and there were no differences between vegetation types.

    Up to the end of the 19th century, travellers in the montane region, both Saami and outsiders, ocularly assessed the plant cover. As a rule, they reported a good supply of reindeer fodder plants, especially lichen species.

    From the end of the 19th century, there began to be observations of severely denuded lichen cover, especially in areas exposed to a veritable invasion of Saami and reindeer from the north-Norwegian and north-Finnish reindeer grazing areas. Incomers from those areas introduced an extensive form of reindeer husbandry, developed to suit conditions on the Finnmarksvidda and in northernmost Finland, where large reindeer herds could readily find grazing on well-demarcated headlands and islands during the snowfree season, without much supervision.

    The conflicts of interest between the incomers, and indigenous Saami who wished to carry on an intensive form of reindeer husbandry, with closely supervised herds, were great. From the beginning of the 20th century, state interventions, in the form of commissions of enquiry and field surveys, were instituted. Their aim was to resolve existing conflicts, to ensure a sustainable access to grazing, and satisfactory profitability. The results cannot be said to have been satisfactory.

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  • 311.
    Eriksson Reuterborg, Izabel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Birds in the City: Bird biodiversity in a boreal northern urban environment2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Urbanization is a growing threat to biodiversity across the globe. As more and more habitats are being destroyed and species extinction rates are rising, we have started looking at how we might decrease this loss of biodiversity. One answer is changing our urban environments to more biodiversity friendly ones. Since conditions within a city and a natural landscape might differ, it is important to understand how landscape variables affect biodiversity in urban areas. The purpose of this study was to investigate how landscape variables (Coniferous/mixed forest, Open uncultivated land, Fields, Deciduous forest, Water, High and Low urban development, and Industrial area) affect bird diversity, richness, and community assembly in a small city in central Sweden. Surveys were conducted on 33 sites. Results from a multiple regression comparing the environmental variables to richness or diversity showed that Water was positively correlated to both diversity and richness. A redundancy analysis (RDA) showed that bird species assemblage was significantly affected by Coniferous/mixed forest, Water, and Fields when the whole bird community was considered. However, when only passerines were included in the RDA, Urban development and Coniferous/mixed forest had the strongest impact. When conservation efforts are made in urban areas, these variables need to be considered since they are correlated with different species and they might not be the same ones that are associated with richness or diversity of birds.

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    Birds in the City
  • 312.
    Eriksson Röhnisch, Kajsa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Purification and Technical Application of a Serine Protease Inhibitor from Solanum tuberosum2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
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    UPTEC X 16 003
  • 313.
    Eriksson Röhnisch, Kajsa
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Bygdén, Evelina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Dahlberg, Jenny
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Nerén, Isabelle
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Rylander, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Wärn, Caroline
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Östergren, Tiolina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Samband mellan virulensgener och VTEC-infektioner: Riskklassificeringssystem för VTEC2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 314.
    Erkers, Julia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Towards automatic smartphone analysis for point-of-care microarray assays2016Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [en]

    Poverty and long distances are two reasons why some people in the third world countries hasdifficulties seeking medical help. A solution to the long distances could be if the medical carewas more mobile and diagnostically tests could be performed on site in villages. A new pointof-care test based on a small blood shows promising results both in run time and mobility.However, the method still needs more advanced equipment for analysis of the resultingmicroarray. This study has investigated the potential to perform the analysis within asmartphone application, performing all steps from image capturing to a diagnostic result. Theproject was approach in two steps, starting with implementation and selection of imageanalysis methods and finishing with implementing those results into an Android application.A final application was not developed, but the results gained from this project indicates that asmartphone processing power is enough to perform heavy image analysis within a sufficientamount of time. It also imply that the resolution in the evaluated images taken with a Nexus 6together with an external macro lens most likely is enough for the whole analysis, but furtherwork must be done to ensure it.

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  • 315.
    Erlandsson, Kristin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Gene expression analysis of the limbic system and identification of subpopulations in the limbic structures of the mouse brain2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 316.
    Esberg, Johannes
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    HABITATSPREFERENSER HOS SVARTMUNNAD SMÖRBULT (NEOGOBIUS MELANOSTOMUS)2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 317.
    Espluga Garcia, Bernat
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The role of ecological networks of interactions on shaping evolvability2024Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    One of the main challenges still confronting biologists is unravelling the mechanismsunderlying the evolution of evolvability — the ability to produce heritable and adaptive phenotypic variation. The impact of ecological factors on evolvability remains largely unstudied. Ecological interactions among populations are a relevant ecological factor shaping biodiversity through coevolution, i.e. the reciprocal adaptation resulting from these interactions. This study adopts a community-wide approach to investigate how the complexity of interaction networks and degree (the number of interacting partners of each species) affect evolvability. Quantifying these metrics represents a monumental practical challenge, which is overcome by harnessing a digital life platform that simulates the coevolutionary process of hosts and their parasites. I found that more evolvable communities are those embedded in a more complex network of interactions. However, within each community, a wide range of evolvability values coexist; an observation not related to specific differences in degree. These results emphasise the role of ecological networks of interaction in shaping evolvability.

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    Popular_science_summary
    The full text will be freely available from 2025-05-01 23:50
  • 318.
    Euler, Nora
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Karolinska Institute.
    Characterization of Allergen-Specific B cells in Allergic Patients: A Potential Biomarker for Allergen Specific Immunotherapy2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The objective of this study was to develop and optimize a method for the detection of allergen-specific B cells in the inguinal lymph node (ILN), to be used for future application in an intralymphatic immunotherapy (ILIT) study aimed at evaluating the potential of allergen-specific B cells as a biomarker for allergen immunotherapy (AIT). The method was first developed for detection of allergen-specific B cells in peripheral blood, and later modified for application for cells retrieved from the ILN. To detect allergen-specific B cells, cells either retrieved from the ILN or from peripheral blood mononuclear cells (PBMC) were incubated with biotinylated allergens, and B cells with an affinity towards the modified allergen were distinguished using flow cytometry. In total, 15 patient volunteers with birch and/or timothy pollen allergy were recruited. Four of the patients were included for comparisons of frequencies of allergen-specific B cells in peripheral blood before and during the birch pollen season. One of the patients was included for the detection of allergen-specific B cells in the ILN. Results indicated that we were successful in detecting allergen-specific B cells in PBMC and ILN. Furthermore, flow cytometric analysis in the peripheral blood demonstrated an increase in the frequency of allergen-specific B cells, plasmablasts (IgE+ and allergen-specific), and the distribution of IgG1 and IgA1 on class-switched B cells during the birch pollen season. Conclusively, our results indicate that the method developed was successful in detecting allergen-specific B cells in both peripheral blood and the ILN and that we were able to detect allergen-driven differentiation of B cells in peripheral blood.

    The full text will be freely available from 2026-09-15 21:00
  • 319.
    Euler, Nora
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    CSF biomarkers related to sleep, cognition and neuroinflammation in patients with Kleine Levin Syndrome2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Kleine Levin Syndrome (KLS) is a hypersomniac disease of episodic nature that affects only 1-5 per million individuals globally. In addition to extensive periods of sleep (> 20 hours) patients experience a wide range of symptoms during an episode, which occur approximately 1-12 times a year with a median of 10 days. The etiology and pathophysiology of the disease is unknown. Diagnostic criteria (The International Classification of Sleep disorders, third addition) rely solemnly on symptomatic characteristics. Misdiagnosis is unfortunately common. The potential of using hypocretin-1, amyloid-beta/tau and the IgG index in the CSF as potential disease biomarkers was investigated. Measurements were taken during the asymptomatic and/or symptomatic phase of the disease. All values were within the normal range. Lower hypocretin-1 values were observed in the asymptomatic phase compared to the symptomatic phase in two of the three patients, although not statistically significant. 

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  • 320.
    Eusebi, Bruno
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Difference in distribution between the White-tailed eagle and the Steller's sea eagle on their wintering grounds.: On Hokkaido, Japan.2021Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The White-tailed eagle (H. albicilla) and the Steller's sea eagle (H. pelagicus) overwinter in the same region of Japan: North-western Hokkaido. To examine how and if these two species compete at their overwintering grounds the following questions were asked: are they evenly distributed over this region and do they compete over space and resources? For the period 2015-2019, I found that the two species were not evenly distributed over the region, and that H. pelagicus is the most common species and does occur over the whole area. At a more detailed study at Lake Abashiri performed in 2019-2020, results showed that H. albicilla was the most common species, and that the distribution of the eagles was determined by the availability of food from anthropogenic activity. The species competed for food resource, fish, and H. pelagicus was the stronger competitor in terms of attacks against heterospecifics. They were less aggressive, but more successful when attacking compared to the White-tailed eagle.

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  • 321.
    Evasdotter, Liselott
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Restoration of a Rich Fen by Top Soil Removal: Temporal and Spatial Responses among Vascular Plants, Bryophytes and Land Snails during 15 years2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Rich fens are calcareous and nutrient poor wetlands with a rich flora of orchids, sedges and mosses. As many as one hundred plant species are rich fen specialists. Many wetlands have been drained historically, and transformed to agricultural land or production forests. Today rich fens cover only 2-3% of the total mire area in Sweden. Rich fen is a rare and valuable habitat also from a European perspective and is protected in the Natura 2000-network. To increase and maintain the biodiversity and ecosystem services rich fens can offer, it is important to increase the rich fen area by restoration and management. Rich fen restoration can be carried out in different ways. In this report the restoration method of top soil removal is investigated. The method has never been tested before in Sweden and therefore it is important to evaluate the suitability of the method for further conservation work.

     

    Before restoration, the study area had been drained, used as arable land and pasture, and finally become abandoned and overgrown by tall eutrophic herbaceous vegetation. An excavator dug away the layer of nutrient rich top soil and then the site was left for spontaneous development. Adjacent to the restored area, there is a small remnant of rich fen. Monitoring of the restored area was performed during the first five years after the restoration. I repeated the monitoring after ten years, and analyzed the long-term succession of plants and snails, in comparison with the status in the reference fen.

     

    The vegetation in the restored parts is approaching the one in the reference fen. For example, the number of rich fen specialists has increased steadily. However, the colonization of bryophytes is slow. They cover at most 20 % in the restored parts, while 80 % in the reference fen, possibly because of dispersal limitation and the fact that the restored area is drier than the reference fen. More species of herbs can be found in the restored parts than in the reference fen. Another difference is the high cover of bare soil in the restored areas, compared to none in the reference fen. Some trees and bushes are growing in the area, primarily birch (Betula pubescens) and different species of Salix. The land snails have successfully colonized the restored areas. After two years the same number of species was found in the restored area, as in the reference fen. The total number of species found in the restored areas was 26, compared to 29 in the reference fen, among them three rare rich fen indicator species.

     

    The results show how the restored site has developed from bare mineral soil to a rich fen site, approaching the species composition of the reference fen. Several species of rich fen specialists among vascular plants, bryophytes and land snails have established in the restored areas. The small rich fen close to the restored area functions as a source from where plants and animals can spread. Overall the restoration shows very positive results, going from bare soil to rich fen vegetation in only ten years.

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  • 322.
    Everett Palm, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre, Swedish Centre for School Biology and Biotechnology.
    Combining Cell Painting, Gene Expression and Structure-Activity Data for Mechanism of Action Prediction2023Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The rapid progress in high-throughput omics methods and high-resolution morphological profiling, coupled with the significant advances in machine learning (ML) and deep learning (DL), has opened new avenues for tackling the notoriously difficult problem of predicting the Mechanism of Action (MoA) for a drug of clinical interest. Understanding a drug's MoA can enrich our knowledge of its biological activity, shed light on potential side effects, and serve as a predictor of clinical success. 

    This project aimed to examine whether incorporating gene expression data from LINCS L1000 public repository into a joint model previously developed by Tian et al. (2022), which combined chemical structure and morphological profiles derived from Cell Painting, would have a synergistic effect on the model's ability to classify chemical compounds into ten well-represented MoA classes. To do this, I explored the gene expression dataset to assess its quality, volume, and limitations. I applied a variety of ML and DL methods to identify the optimal single model for MoA classification using gene expression data, with a particular emphasis on transforming tabular data into image data to harness the power of convolutional neural networks. To capitalize on the complementary information stored in different modalities, I tested end-to-end integration and soft-voting on sets of joint models across five stratified data splits. 

    The gene expression dataset was relatively low in quality, with many uncontrollable factors that complicated MoA prediction. The highest-performing gene expression model was a one-dimensional convolutional neural network, with an average macro F1 score of 0.40877 and a standard deviation of 0.034. Approaches converting tabular data into image data did not significantly outperform other methods. Combining optimized single models resulted in a performance decline compared to the best single model in the combination. To take full advantage of algorithmic developments in drug development and high-throughput multi-omics data, my project underscores the need for standardizing data generation and optimizing data fusion methods. 

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  • 323.
    Everett Palm, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    CRISPR-Cas9 som behandlingsmetod för herpeskeratit orsakad av herpes simplexvirus typ 12021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den snabba utvecklingen av det nya genredigerande verktyget CRISPR-Cas9 har öppnat dörren för behandlingen av svåra, virusorsakade sjukdomar. Herpes simplexvirus typ 1 (HSV-1), en av de mest vanligt förekommande virus i världen, kan etablera sig latent i känselnervceller. Stressfaktorer kan orsaka herpeskeratit, som är en sekundär infektion av ögat vilket leder till inflammation och potentiell ärrbildning. Vid upprepade återfall kan herpeskeratit resultera i synnedsättningar och i allvarligare fall blindhet, och därför anses det som en stor samhällsbörda. 

    Denna uppsats undersöker förutsättningarna att CRISPR-Cas9 i framtiden ska användas för att effektivisera behandlingen av herpeskeratit. Detta görs först genom att beskriva hur HSV-1 infekterar människokroppen, etablerar latens och skadar hornhinnan. Sedan introduceras utvecklingen av CRISPR-Cas9 som ett molekylärt verktyg där dess fördelar och nackdelar beskrivs. Slutligen sammanfattas de tre olika tillvägagångssätten av forskare som undersöker möjligheten att skapa en CRISPR-Cas9-baserad behandling. 

    Den första metoden baseras på användningen av CRISPR-Cas9 för att dämpa virusreplikation vilket resulterar i att konsekvenserna blir lindrigare vid eventuella återfall. Detta alternativ har visat sig vara framgångsrikt in vitro och det kringgår en del utmaningar gällande leveranssystemet, men är begränsad i sina användningsområden. Den andra metoden baseras på att redigera känselnervceller så att de konstant utsöndrar CRISPR-Cas9 samt relevanta guide- RNA för dämpningen av virionbildandet likväl som förebyggandet av en primärinfektion. I praktiken blir detta svårt att tillämpa som behandlingsmetod på grund av ett antal tekniska svårigheter. Det tredje alternativet är att klyva det latenta HSV-1 genomet. Detta skulle omöjliggöra en sekundärinfektion. In vitro-experiment har visat att det är möjligt, men svårigheter med leveranssystem och effektiviteten har gjort det problematiskt att dra några relevanta slutsatser om CRISPR-Cas9 är rätt väg eller inte. Andra genredigerande enzymklasser, exempelvis meganukleaser, har haft större framgång i musmodeller. Forskningen gällande CRISPR-Cas9 är vid ett tidigt stadium, men har väckt stort intresse inom forskningsvärlden. Med fortsatt optimeringen av CRISPR-Cas9, och dess framgång i andra virussammanhang är det troligt att CRISPR-Cas9 eventuellt kommer vara en del av lösningen för att bota herpeskeratit. 

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  • 324.
    Everitt, Turid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Karolinska Institutet, Medical Biochemistry and Biophysics/SciLifeLab.
    Utilizing data from a new, quantitative ChIP-sequencing method to investigate the dynamics of histone H3.32018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    DNA is a key component of almost all cells, but it is not the sole determinant of the cellular functions and features. A great number of histones, transcription factors and other proteins interact with the DNA, regulating fundamental processes such as DNA accessibility and gene expression. Perturbations of these interactions are associated to a wide range of diseases. An example is the histone variant H3.3, which is normally involved in prevention of genomic rearrangements during mammalian development. Mutations in the H3.3 gene have been shown to be related to pediatric brain cancer forms. Studying this histone variant and other protein-DNA interactions is important in order to understand cellular processes as well as causes of diseases. This has commonly been done through a sequencing method called ChIP-seq, which however does not normally capture the dynamics of the interactions. Therefore a new method called MINUTE-ChIP has been developed, which in combination with a special type of pulse-chase experiment adds a time dimension to the analyses. In this project, data from this new method has been analyzed in order to investigate the dynamics of histone H3.3. In addition to calculating the rates of incorporation and release from the DNA, tools for visualizing the data in interactive plots have also been developed. These calculations and tools facilitate the interpretation of the histone H3.3 data and can in the future be used for analyzing data generated by similar experiments for other chromatin factors.

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  • 325.
    Everling, Sanne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The effect of temperature on the interaction between larvae of a native and a range expanding dragonfly species2021Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Climate change might affect the distribution of species; therefore, it is important to anticipate the imminent impact of climate change. Even though climate responses have the potential to affect species interactions, most models on the effect of climate change on species distribution assume that species respond to climate individually. Hence studies on competition effects are needed. In this study, I estimated growth, mortality, and behaviour (prey capture success, activity, exploration and boldness) at 20° C and 23° C at intra- and interspecific competition conditions in larvae of a native and a northward dispersing dragonfly. The results showed that the northward expanding Sympetrum fonscolombii had a higher growth and survival rate compared to the native Sympetrum vulgatum at interspecific conditions. At intraspecific conditions the results showed that temperature had no significant effect on the performance of S. fonscolombii, but S. vulgatum showed both a higher growth rate and a higher mortality at 23 ° C. A significant difference between temperatures within prey capture success rate was found in S. vulgatum only, during the second observation period. There was a correlation between activity and exploration in both species, between prey capture success rate and activity during the third observation round in S. vulgatum, and between prey capture success rate and boldness during the first observation round in S. fonscolombii. No other behaviours were correlated. Prey capture success rate was shown to be repeatable in both species, while boldness was repeatable in S. vulgatum only. The behavioural results suggests that behavioural traits are relatively plastic over ontogeny in both species, possibly caused by behavioural variation within each instar. Additionally, boldness, but not activity and exploration, might aid S. fonscolombii in their northward expansion. The majority of these results were similar at both temperatures and indicate that S. fonscolombii has a higher capacity to tolerate climate change, and their presence might negatively impact the performance of S. vulgatum.

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  • 326.
    Fahim, Dipita
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Immunology, Genetics and Pathology.
    The role of ribosome biogenesis in proneural-to-mesenchymal transition in glioblastoma multiforme2021Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
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  • 327.
    Falck, Julius
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The unique singing behaviour of an African lark: song variation in the Monotonous Lark Mirafra passerina2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Bird song can teach us much about animal behaviour and evolution. This study presents a type of song variation that has yet to be extensively studied. The Monotonous Lark Mirafra passerina is a nomadic lark with an iconic, simple and repetitive song. It has been noted to have a large song variation between irruptions, but limited variation in the same irruption, a behaviour previously, to my knowledge, unknown in the avian world. This study aims to describe the song and analyse the variation within and between irruptions, and try to explain the underlying mechanisms behind the variation. This article studies the song by analysing song material spanning 30 years with 140 samples, most from South Africa. The whole song and the syllables were measured. A custom edit distance and Euclidean distance were used to quantify song differences. Principal component analysis was performed on both syllable measurements and the whole song. The results showed a larger song variation between irruptions compared to within irruptions. It also showed that the song varies greatly between irruptions; however, a general pattern of how the song is structured was found. In addition, some indications of song retention between years were noticed. This study describes a unique example of avian behaviour that can broaden our knowledge of animal communication and its evolution and development.

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  • 328.
    Fan, Yuting
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Radiobiology of The Developing Brain: Co-exposure to radiation and anesthetics2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 329.
    Fanny, Törnkvist
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    SKÖTSELPLAN FÖR NATURRESERVATET HELGES HAGE2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this study was to prepare a management plan for the future nature reserve Helges hage in Eksta, Gotland. The area has a long continuity as a woodland and has been used as pasture and for selective logging. This type of forestry practices creates a dynamic, heterogeneous landscape with a rich biodiversity. In Helges hage many unusual soil fungi and two endangered grass species have been found. Grazed woodlands is one of the habitats that has decreased most in Sweden the last century as a result of the modern forestry. Helges hage has not been grazed since the 1960 and the forest understory is now overgrown by shrubs and saplings. In order to preserve the natural values of a grazed woodland it is required to reintroduce grazing and that parts of the forest is thinned in order to create a less dense forest with more light reaching the ground.

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  • 330.
    Farhat, Crystal Marian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Karolinska Institute, Department of Oncology-pathology.
    Mechanistic study of one-carbon folate cycle enzymes in DNA repair: Determining the role of MTHFD1 and MTHFD2 in cancer cell survival2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Cancer cells are characterized by several hallmarks, two of which include metabolic reprogramming and genomic instability. Due to their high proliferation demand, cancer cells need to synthesize nucleotides at a higher pace compared to healthy cells. The one-carbon folate metabolic pathway helps transformed cells meet proliferation demands by mediating nucleotide/thymidylate biosynthesis and de novo purine synthesis, where key enzymes include methylenetetrahydrofolate dehydrogenase 1 and 2 (MTHFD1 and MTHFD2). MTHFD1 is the cytosolic enzyme of the 1C pathway and MTHFD2 is the mitochondrial enzyme contributing to the folate cycle through driving nucleotide biosynthesis. Here, we show that MTHFD2 also has a non-canonical function in DNA repair. This study aims to understand the contribution of MTHFD1/2 in the DNA damage response (DDR) in the presence of DNA double-strand breaks (DSBs) in colorectal cancer cells. It further aims to study the effects of MTHFD1/MTHFD2 inhibitors synthesized by the Helleday group. Knockdown (KD) of MTHFD1 /MTHFD2 using siRNA coupled with ionizing radiation (IR) and colony formation assays (CFA) were used to determine cell viability. Loss of cell viability and proliferation was observed upon mthfd2 gene KD. Changes in DDR protein induction were observed in MTHFD2 KD cells, using Western blot analysis. Confocal analysis was used to detect and quantify sites of DSBs in wildtype SW620 and MTHFD2 -/- cells post IR, where MTHFD2-/- cells were shown to sustain more damage, indicating reduced DNA repair capacity. Subcellular fractionation data revealed that MTHFD1/MTHFD2 inhibitors interacting with nuclear and cytosolic MTHFD proteins and inducing replication stress.

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  • 331.
    Fei, Mengjie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Effect of light regime on Drosera Rotundifolia2015Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The perennial carnivorous plant Drosera rotundifolia with its red leaves has interested scientists for ages. The red colour of its leaves was for long time believed to help in luring prey insects, but later studies have indicated that it might also function as an alert to pollinators and to avoid over capture of pollinators. Either of the functions is important for the carnivorous investment of D. rotundifolia. As the red colour in the leaves is determined by the accumulation of the UV-positive compound anthocyanin, it is possible that the leaf colouration is affected by the surrounding light regime. Therefore, it would be useful to understand the function of the red colouration and how it relates to the local light regime. In my study, leaf colour varied a lot under different light regimes, however with no significant pattern along light gradient. Leaf size exerted an effect on leaf colour, as smaller leaves were redder. In addition, effects of light on morphological traits were detected. With an increase of sun exposure, D. rotundifolia had higher specific leaf dry mass. Plants had larger total leaf area on plots with intermediate vascular plant vegetation height. Exposure to light and insects and nutrient conditions indicated by vascular plant height could in combination affect the growth of leaves of D. rotundifolia. Also the competition of nutrient by Sphagnum fuscum (Schimper) H. Klinggräff could be one of the factors influencing the leaf area of D. rotundifolia. Thus, this study found an effect of light on morphological traits of D. rotundifolia, but lacked evidence on colouration. Further studies could be carried out with a more detailed description of the light regime when illustrating the light effect on colouration of leaves of D. rotundifolia.

  • 332.
    Fermér, Elin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Selection for Antibiotic Resistance Below Minimal inhibitory concentration in Biofilm2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Antibiotics are today one of the most important cornerstones in modern healthcare when it comes to treating bacterial infections. It is an asset human kind have been leaning on for the last century, but excessive and widespread misuse of antibiotics have left deep scars in the form of multi resistant pathogenic strains of bacteria that we soon will not be able to treat. A lot of research have been invested in understanding the mechanisms and spread of resistance within bacteria living in planktonic form, overlooking the fact that there are more lifestyles that causes problems. In this study, focus has been put on antibiotic resistance within bacteria living as biofilms, a lifestyle that causes problems in chronic infections and prosthetics/medical implants. By constructing resistant mutants derived from a biofilm forming strain of Escherichia coli, the minimal selection concentration has been investigated in both planktonic and biofilm assays for Streptomycin and Ciprofloxacin. By comparing the results, it is possible to evaluate if and how the antibiotic resistance properties differ between the two lifestyles. Focus has been put on concentrations of antibiotics below the minimal inhibitory concentration with the objective to see how selection of antibiotic resistant mutants take place with the susceptible strain still growing, although with reduced growth rate. The hope is that the results gained in this study will provide a foundation for future research regarding antibiotic resistance in biofilms, and be part of the solution to the excessive resistance problem before it is too late.

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  • 333.
    Fernberg, Jenny
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Growth Dynamics, Antibiotic Susceptibility and the Effect of Sublethal Ciprofloxacin Concentrations in Susceptible and Resistant Escherichia coli in Biofilm2019Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Instead of planktonic growth in nature, many species of bacteria form biofilm to survive in harsh conditions. Although many chronic bacterial infections are caused by bacterial species in a biofilm lifestyle, previous research has focused on studying antibiotic resistance in planktonic growth. Here we used a modified MBEC assay, i.e. biofilm growth on pegs, to determine Escherichia coli biofilm inhibitory concentrations (BIC) of ciprofloxacin, streptomycin and rifampicin and to study the minimal selective concentration (MSC) for ciprofloxacin in E. coli biofilm. We could observe high inhibitory concentrations for all antibiotics in the biofilm pre-formed in media without antibiotics compared to the biofilm formed in antibiotics. We also show preliminary result indicating that sublethal concentrations of ciprofloxacin lead to the selection of ciprofloxacin resistant mutants in biofilm and that the selection level is lower than what was observed in planktonic growing E. coli. With more knowledge in how the biofilm formation precedes in different antibiotic settings, the treatment for chronic biofilm infections used today could be evaluated and changed so that the infections could be eradicated.

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  • 334.
    Fernández Mestre, Clàudia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Drivers of flower size evolution in the selfing species Arabidopsis thaliana2023Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The influence of pollinators on the evolution of flower morphology has been extensively explored. Yet, the effect of other ecological factors, such as genetic drift, environmental filtering, and allometric constraints, gained less attention. In this study, we addressed the importance of those drivers in a predominantly selfing species. 400 worldwide Arabidopsis thaliana accessions were gathered and grown in semi-controlled climatic settings to explore the association between flower organ size, genotypes, and habitats. In our dataset, petal area was the most variable trait. Petal size was phenotypically and genetically correlated with other flowering structures, but no genetic allometry constraints were found to affect petal size evolution. The negative correlation of petal size with fitness and the traces of selective constraints in petal associated genes suggest that petal size is currently under selection in this species. We found paucity of genotypes harbouring large petals at low suitability regions, which points to the presence of environmental filtering. The novelty of this project relies on the pluralistic integration of factors studied and highlights the role of the climate on flower size evolution. Our results suggest that resource allocation is an important driver of flower size evolution in self-fertilising species but that its effect is largely determined by local environmental pressures.

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  • 335.
    Ferrer, Samuel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    STAIRS: Data reduction strategy on genomics2019Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background. An enormous accumulation of genomic data has been taking place over the last ten years. This makes the activities of visualization and manual inspection, key steps in trying to understand large datasets containing DNA sequences with millions of letters. This situation has created a gap between data complexity and qualified personnel due to the need of trading between visualization, reduction capacity and exploratory functions, features rarely achieved by existing tools, such as SRA toolkit (https://www.ncbi.nlm.nih.gov/sra/docs/toolkitsoft/), for instance. A novel approach to the problem of genomic analysis and visualization was pursued in this project, by means of STrAtified Interspersed Reduction Structures (STAIRS). Result. Ten weeks of intense work resulted in novel algorithms to compress data, transform it into stairs vectors and align them. Smith–Waterman and Needleman–Wunsch algorithms have been specially modified for this purpose and the application brought about statistical performance and behavioural charts.

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  • 336.
    Ferro, Giovanni
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Improving antibody-based immunotherapy protocols in vitro: Study on optimization of antitumor immunity by antibody-dependent phagocytosis with the monoclonal antibody rituximab2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The monoclonal antibody Rituximab (RTX) has been widely and successfully used to treat non-Burkitt B cell lymphoma in human patients. The combination of immunotherapy with low-dose chemotherapy has increased the success of the treatment and translated into increased patients’ survival. On the other hand, many patients react differently to the chemotherapy, the antibody treatment, and the combination of the two, translating into a need for studies that evaluate strategies to improve response and enhance antibody-dependent phagocytosis by the patient’s immune cells. In the present study, I investigated separately four different lymphoma B cell lines grown in 3D tumor spheroid models which better represent cancer in vivo than the conventional in vitro 2D cell suspensions. These tumor models were treated with the monoclonal antibody Rituximab in the FDA approved IgG1 isotype form, with other non-approved isotypes and with a combination of them. The RTX-opsonized lymphoma models were then co-cultured with IFNγ activated monocytes, followed by an evaluation of the tumor cell killing efficacy by flow cytometry. The use of the chemotherapeutic agent staurosporine (RTX) in combination with RTX was also investigated. RTX isotype IgG3 proved to induce the highest percentage of phagocytosis of all the investigated tumor cell lines, both in 2D suspension and in 3D spheroid models. The phagocytosis efficacy increased when in combination with previous chemotherapeutic treatment with STR for all cell lines, with slight variation between them. We identified CD47 as a cell surface receptor that might have a role in this effect. CD47 is part of the CD47-SIRPalfa axis, used by somatic cells and cancer cells as a “don’t eat me” signal to prevent being engulfed by the body’s immune cells. We found a positive correlation between the expression of this surface receptor and the change in phagocytosis percentage when combined with apoptosis inducing agents. Our data matches previous works that studied the role of CD47 and how it becomes non-active, or hidden, on apoptotic cells. We suggest that apoptosis inducing agents should be paired with RTX immunotherapy for the treatment of tumors expressing large amounts of CD47 on their surface. The usage of CD47 as a prognostic biomarker in B-cell non-Hodgkin lymphomas (NHLs) has the potential to dramatically change how we use CD20-targeting antibodies and needs to be further investigated in future studies.

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  • 337.
    Filek, Klara
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Contact-dependent growth inhibition in Escherichia coli EC932018Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Microorganisms live in complex communities and interact either through secreting soluble molecules or by delivering effectors in a contact dependent manner. Microbial interactions range from cooperative to competitive. Contact-dependent growth inhibition (CDI), discovered in Escherichia coli EC93, is becoming increasingly studied, as this mode of interaction seems to be widespread among proteobacteria. CDI is mediated by cdiBAI genes which encode for a two-partner secretion system; i.e. CdiB is an outer membrane protein that transports CdiA to the surface of the cell. CdiA can interact with a specific receptor on a target cell and deliver a toxin localized in its C-terminal domain to the target cell. CdiI is a small immunity protein that neutralizes the toxic effect of CdiA toxin. Recently, evidence from our research group has shown that E. coli EC93 harbours two cdi loci. The first cdi locus has been extensively studied but the role of second locus remained unknown. In this study we wanted to elucidate the activity and the role of second E. coli EC93 cdi locus in intra-strain bacterial interactions. Bacterial competitions of E. coli EC93 wild type versus E. coli EC93 targets that had deletions for one or both cdi loci showed that the second locus is indeed active in inhibiting the targets, albeit to a lesser extent than the first. The toxic activity of the second cdi-locus was neutralized specifically by the second immunity protein. The expression of both these systems is higher under carbon starvation conditions than in nutrient rich conditions. Unfortunately, we could not elucidate the mechanism of toxicity for the second cdi locus toxin. Taken together, our results show that E. coli EC93 actively uses both of its cdi loci during bacterial interactions and that these systems are more active during stressful conditions.

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    CDI in EC93
  • 338.
    Filipe, Diogo
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Acquired and lost structure-functions of non-enveloped and enveloped viruses2022Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Viruses are biological entities that constantly affect the world around us and in many cases they can harm the health of humans and negatively impact food production, in agriculture andfisheries. The project concept is that, through the structural studies of viruses that infectsimple hosts, it is possible to point out structural features that are unique and conserved inviruses, that infect human, other animals, and crops, in the same phylogenetic lineage. Theseunique features have functionally been acquired, and are therefore potential drug and vaccinetargets. Standing on this concept, we aim to study three groups of pathogenic viruses: (i)Protozoan/Yeast Totiviridae and metazoan totivirus-like viruses, (ii) Invertebrate flavi-likeand vertebrate Flaviviridae viruses, and (iii) Invertebrate Mesoniviridae and vertebrateCoronaviridae viruses.First, we focused on acquired capsid structures of the totivirus-like Omono River Virus(OmRV). Unlike yeast Totiviridae viruses, the totivirus-like OmRV capsid presents surfaceprotrusion proteins, which are expected to be crucial for its extracellular transmission. Theinteraction between the capsid and the protrusion proteins is hypothesized to be largelymediated by amino acid residue T365 of the protrusion proteins. To clarify the function ofthese protrusion proteins we have successfully developed molecular tools, which are arecombinantly expressed protrusion protein and an OmRV infectious DNA clone with aT365A mutation. Although the excess of the protrusion proteins does not remarkably affectthe infectivity and binding capabilities of the OmRV particles, the OmRV with the T365Amutation shows a significantly reduced infectivity. Assuming that the infectivity was partiallyeliminated by the mutation, a putative transmission mechanism is associated with theprotrusion proteins. However, it is still under debate whether the protrusion proteins are anessential factor for extracellular transmission. Additionally, a new method was preliminarilyused for observing the interaction between the OmRV capsid and protrusion proteins usingdifferential scanning fluorimetry. The findings and the established methods can contribute tothe understanding of molecular mechanisms present in other pathogenic totivirus-like virusesthat affect fish, such as the salmon piscine myocarditis virus (PMCV).Secondly, we focused on acquired surface structures of vertebrate Flaviviridae andCoronaviridae viruses. Unlike the invertebrate flavi-like and Mesoniviridae viruses, thevertebrate viruses have acquired surface structures that are expected to be critical for evadinghosts’ adaptive immunity. To discover these acquired surface structure, it is necessary todetermine the surface structure of the invertebrate flavi-like and Mesoniviridae viruses. Herewe report the successful expression and purification of the invertebrate flavi-like Southernpygmy squid flavivirus (SpsFV) precursor/membrane-envelope (prM-E) protein and theMesoniviridae Nam Dinh virus (NDiV) p2a spike protein. The established expression andpurification system can be further used to resolve their structures using cryo-EM singleparticle analysis in future studies.

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  • 339.
    Finnsdóttir, Rán
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. The Soil Conservation Service of Iceland.
    Effects of sheep grazing on plants adapting to climate change and rising temperatures2020Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Global warming is expected to affect the arctic harsher than other regions of the globe. Many

    plant species will face conditions that contradict their adaptations in a warming climate.

    Changes in habitat can lead to drastic changes in biodiversity as well as exerting a strong

    selective pressure for plants to evolve and adapt quickly. Herbivore grazing in the arctic also

    affects plant ecosystems e.g. by lowering biodiversity and changing species composition and

    may influence their response to warming.

    The aim of this study was to examine whether grazing influences plants’ adaptation to rising

    temperatures. Geothermally warmed areas have been used as in situ proxy systems for effects

    of warming climates on ecosystems. Grændalur, a geothermally warmed valley in southwest

    Iceland, was used as a study site to explore the effects of warming and grazing on ecosystems.

    Three soil temperature gradient transects were established there and each transect has six

    fenced-off plots, at different soil temperatures (ambient +0, +1, +3, +5, +10 and +20°C), and

    paired plots outside the fence that were grazed by sheep. Species richness, evenness,

    Shannon-Wiener and Simpson’s diversity, species cover, and composition as well as plant

    height were measured in these plots inside and outside the fence. In addition, flowering and

    vegetative Ranunculus acris (meadow buttercup) individuals were counted in each plot to

    assess grazing effects on flowering success.

    Grazing did not influence the plant community response to warming. Rising temperature

    decreased species richness and both Shannon-Wiener and Simpson’s diversity, and drove

    changes in community composition. Plant height increased with rising temperatures but

    decreased with grazing. Grazing also significantly reduced R. acris flowering. These results

    highlight the need for sustainable grazing management in Iceland, as well as the significance

    global warming has for plant communities.

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    Thesis_Msc_Rán Finnsdóttir
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    Popular summary_Rán Finnsdóttir
  • 340.
    Fjällskog, Tora
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Phosphoserine, a potential bioink additive for enhanced cell adhesion and survival2024Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    The full text will be freely available from 2025-02-07 08:00
  • 341.
    Flinkfeldt, Linnea
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    High throughput pipeline for rapid antibiotic susceptibility testing and ID of bacteria from blood cultures2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Rapid and accurate species identification and antibiotic susceptibility testing are of great importance for patients with sepsis and to stop over- and misuse of antibiotics contributing to antibiotic resistance. QuickMIC™ is a rapid antibiotic susceptibility testig system based on a microfluidic technology solution developed by Gradientech that measure MICs on bacteria from positive blood culture bottles. By combining QuickMIC™ with a rapid system for detection and identification, the time to detection, identification and antibiotic susceptibiolity testing could be shortened with days compared to pipelines used today which could mean the difference of life and death for patients. The T2Bacteria® panel and T2Dx® instrument developed by T2 biosystems is an FDA-cleared test for rapid detection and identification of bacteria from whole blood based on magnetic molecular resonance technology. The time to result of the T2Dx® instrument is 3-4 hours and the time to result for QuickMIC™ is 2-4 hours. In this project, the possibilities and benefits of such a pipeline have been studied by comparison to a pipeline typically used today. Time, accuracy and practical aspects have been investigated during the project and the results are promising for future further studies.

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  • 342.
    Fogelström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    DNA barcoding of freshwater fishes in Matang, Malaysia2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
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    DNA barcoding of freshwater fishes in Matang
  • 343.
    Forngren, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Educational Sciences, Department of Education.
    Kognitiv neurovetenskap i skolan2019Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Utvecklingen av nya metoder för att studera hjärnans struktur och funktion har lett till ny förståelse om kognition. Inom kognitiv neurovetenskap studeras sambandet mellan hjärnan och tänkandet, där inlärning ingår. Hur inlärning fungerar är väsentligt för att utbildning tillgodogörs. Denna litteraturstudie är baserad på delar av den kognitiva neurovetenskapen som berör olika aspekter av vad skolan och lärare kan ha nytta av för att främja elevers inlärning. Hjärnans olika funktioner kan ofta kopplas till olika regioner i hjärnan, och hippocampus samt främre hjärnbarken är två viktiga regioner för både minnesbildning samt framplockning av minnen. Främre hjärnbarken är dessutom den del av hjärnan där de exekutiva funktionerna som har stor betydelse för inlärning är lokaliserade. En viktig förutsättning för inlärning är att hjärnan är plastisk, den kan förändras både strukturellt och biokemiskt. Hjärnan är plastisk hela livet, men fram tills 25-årsåldern då hjärnan fortfarande utvecklas sker större förändringar, vilket har betydelse för såväl inlärning som beteende. Stress kan genom bland annat synaptisk plasticitet påverka inlärning på ett negativt sätt över tid, samtidigt som det även direkt hämmar vår förmåga både att lära oss och att minnas. Till exempel kan stress hämma våra exekutiva funktioner, varav arbetsminnet är en sådan funktion som är betydande för inlärning. Många ungdomar idag lider av psykisk ohälsa, och upplevelser av negativa emotioner bidrar till att hjärnan och kroppen upplever stress. För att öka elevers uppmärksamhet är det därför viktigt med ett klassrum där det är lugnt och alla känner sig trygga. Elevers uppmärksamhet och inlärning kan även påverkas genom motivation, som i hjärnan är lokaliserat i en del av belöningssystemet. Det är även förmågan att lära sig genom återkoppling, som är ett effektivt sätt att skapa inlärning. Hjärnan lär sig genom att associera ny information till tidigare lagrad kunskap, vilket är bra att tänka på framförallt när ny kunskap ska presenteras. Bra sömn och fysisk aktivitet är två faktorer som är viktiga för minnesbildningen men som kan kännas svåra att påverka som lärare, samtidigt som det inte är helt omöjligt. Även mindfulness kan implementeras och bidra till både bättre välmående och inlärning. Den kognitiva neurovetenskapen kan på flera sätt tillämpas i skolan för att främja elevers inlärning.

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  • 344.
    Forngren, Sofia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Vad säger neurobiologisk forskning om motivationens betydelse för inlärning?2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Kan motivation till att lära sig gå att se genom avbildningar av hjärnan? Finns det någraneurobiologiska stöd för att det dessutom skulle kunna påverka minnesbildning? Tidigareforskning har visat att aktivering av belöningssystemet och ökade nivåer av signalsubstansendopamin kan gynna minnesbildning. I denna översiktsartikel behandlas studier som berörmotivation ur olika psykologiska aspekter och hur det påverkar det deklarativalångtidsminnet. Olika hjärnavbildningsmetoder där dopaminerga regioner och hippocampushar varit centrala, tillsammans med olika inlärningsuppgifter och psykologiska tester talar föratt motivation är en viktig faktor för inlärning. Dessutom visar flera av studierna att positivåterkoppling har en bättre effekt på inlärning jämfört med negativ återkoppling.

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  • 345.
    Forslund, Annica
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Investigation of developmental neurotoxic effects of exposure to a combination of methylmercury and chlorpyrifos2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
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  • 346.
    Forsskåhl, Sophia Katarina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Göteborg Universitet, Biomedicinska institutionen, Avdelningen för mikrobiologi och immunologi.
    Altered expression of inflammasome components in inflammatory bowel disease2019Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The inflammasome complex is a multiprotein complex that may play a role in the pathogenesis of inflammatory bowel disease (IBD) by secreting the inflammatory cytokines interleukin (IL)-1β and IL-18, and inducing pyroptosis, as a response to signals through several inflammasome sensors.

    This study looked at the expression of several inflammasome components in the ileum and colon of patients suffering from IBD. The inflammasome sensors NLRP1, NLRP3, AIM2 and pyrin were upregulated in whole intestinal tissue of IBD patients, particularly in the colon. NLRP6 expression was increased in the colon of Crohn's disease patients, but not ulcerative colitis patients relative to colon of controls, and was reduced in the ileum of Crohn's disease patients compared to control ileum. Expression of caspase-1 and IL-1β, but not IL-18, were also increased in ileum and colon tissue from Crohn's patients.

    To identify the cell type where inflammasome expression was altered in Crohn’s disease, transcription of inflammasome subunits in intestinal tissue enriched for epithelial cells or lamina propria (LP) cells was analysed. These analyses indicated that LP cells have greater expression of the inflammasome sensors NLRP1, NLRP3, AIM2 and pyrin relative to epithelial cells, both during disease and in control tissue. Moreover, LP cells from Crohn’s patients have higher expression level of NLRP1, AIM2 and pyrin than LP cells from controls. In contrast the inflammasome sensor NLRP6 was more highly expressed by epithelial cells relative to LP cells in general, and NLRP6 expression in LP cells from IBD patients was lower than that observed in LP cells from controls.

    The observed differential expression of inflammasome components in controls versus IBD intestine and in different cellular fractions of intestinal tissue highlight the importance of understanding the role of the inflammasome in IBD and hints at the possibility of targeting the inflammasome pathway as a future treatment strategy.

  • 347.
    Forssten, Moa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Effects of early exposure to fluoxetine on behavioural development in zebrafish2024Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Many pharmaceuticals are stable molecules and after human excretion they enter the wastewater facilities where roughly 60 % is removed. The remaining residues will affect the concentration in close by streams and at the effluent, where fish like to spawn. Therefore, the development and behaviour of aquatic life is potentially at risk. I studied the effects of fluoxetine on zebrafish (Danio rerio) younger than 1 month which were exposed from fertilized egg until 6 days post fertilization (dpf). The concentrations tested were related to previous findings in the effluent waters, 1 µg/L and 100 µg/L. With Daniovision it was found that there were most differences at 10 dpf, all three variables tested (distance moved, velocity and time in zone) showed differences between the high and low exposure. These results shed light on the rising problem with anti-depressants in the aquatic environment, affecting fish behaviour, withpotential effect on fish population and in the species.

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    Effects of early exposure to fluoxetine on behavioural development in zebrafish
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    Kan zebrafisk bli mindre stressade av våra antidepressiva läkemedel?
  • 348.
    Fortier-Dubois, Étienne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Late Devonian vertebrates from Siberia: a synchrotron microtomography study of bone bed material2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This is an investigation of new vertebrate fossil material from the Late Devonian locality of Ivanovka, Uryup River, Siberia. This bone bed material, circa 375 million years in age, represents a unique opportunity to fill a gap in our understanding of Late Devonian diversity, biogeography, and vertebrate evolution: Siberia, at the time, was an independent continent, and yet its fauna remains virtually unknown in comparison with the other paleocontinents, Euramerica and Gondwana. Using synchrotron microtomographic scanning, a non-destructive technique that has never, to our knowledge, been applied to bone bed material, we obtained 3D image stacks that were then modelled to yield triangle meshes representing the bones in three dimensions. These meshes could then be identified, described, and interpreted. Many of the discovered bones belong to the poorly known genus Megistolepis Obruchev 1955, potentially allowing a radical increase in knowledge regarding this taxon. Other material includes lungfish and possible fragments of limbed tetrapods, though the evidence of the latter is scarce. A discussion of the advantages and disadvantages of synchrotron microtomography for the study of bone bed material concludes the paper. 

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  • 349.
    Fransson, Lina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Fine scale habitat and movement patterns of javan slow loris (Nycticebus javanicus) in Cipaganti, West Java, Indonesia2018Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Today biodiversity is rapidly decreasing and an increasing number of threatened species live in modified and human dominated landscapes. Therefore it is essential to learn more about how species cope with the changes of their habitat. The focus of this study lies on a primate species, the critically endangered Javan slow loris (Nycticebus javanicus), endemic to the densely populated island of Java, Indonesia.  In cooperation with the Little fire face project in West Java, I used a step selection function (SSF) framework, to understand how landscape structure affects the movement of Javan slow lorises within a fragmented mountain-agroforest landscape of Cipaganti, West Java.

    To investigate the movement and fine scale habitat selection of slow lorises I used one hour locations of 6 radio-collared slow lorises. The habitat and vegetation of observed and random steps was investigated in multiple variables such as presence of food trees and signs of human disturbance. For the analysis I paired observed steps (1h relocations) with 3 random habitat locations and used a conditional logistic regression to parameterize the SSF, which represents the probability of a focal slow loris to select a given step as a function of the habitat and vegetation factors surveyed. In average the slow lorises travelled about 450 m each night and most frequently they used a step length of about 0 – 50 m.

    My result reveals that slow lorises fine scale habitat selection is positively influenced by the presence of trees and tree trunk cover (indirect increasing the canopy cover and connectivity). They are also to a high extent positively affected by the presence of a feeding tree species, Calliandra calothyrsus. Surprisingly slow lorises selected steps associated with a higher number of fields (fields may indicate an increased biodiversity within the location). The results also indicate that slow lorises are limited in their movement by the presence of fields or rivers, which indicates that slow lorises are negatively influenced in their movement by a declining ability to move and forage within Cipaganti. I found no significant differences between sexes in their distance travelled.

    The recommendation for future conservation of slow lorises in Cipaganti is to prevent further habitat loss and fragmentation through activities that protect or maintain the present suitable slow loris habitat. Further research is needed to increase the knowledge of these primates’ abilities to live in this modified landscape. 

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  • 350.
    Fransson, Lina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Äggläggningspreferenser för honor av väddnätfjäril, Euphydryas aurinia, på området Bälsalvret, Gotland2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study aims to get a better understanding of the oviposition-behaviour of the butterflyMarsh Fritillary (Euphydryas aurinia), in the area Bälsalvret on the Island of Gotland. Thestudy may provide helpful information to aid the conservation of the species in the area andalso provide overall knowledge about the female’s preferences when it comes to choosingmicrohabitat and host plant for their eggs.The analysis of the microhabitat preference for oviposition by the Marsh Fritillary showedthat eggs were predominantly laid on large-sized host plant individuals with a warmermicroclimate; with a preference for the rosette diameter, the length and the width of the leafand the number of Succisa pratensis individuals in the vicinity. This indicates that thefemale’s priority is to place the eggs at the most optimal place for their offspring’s survivaland growth.

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